The present invention relates generally to a system and method for measuring power during an activity such as legged locomotion. Using power as a means to quantify the level of effort or work exerted over time during activities such as walking or running may be useful in the fields of physical therapy, medicine, athletics, and other physiological research.
Conventional activity monitoring systems focus on the metrics of speed, distance traveled, and heart rate. Such conventional systems have limitations. For example, at a constant level of effort, speed and heart rate can vary widely due to other factors. Heart rate may vary due to a level of hydration or state of recovery, temperature and elevation. Speed may vary with slope of the surface being traversed, such as when a runner is going uphill. Wind speed or other environmental conditions also affect speed.
Conventional activity monitoring systems include sensors located in or on footwear to detect speed and/or distance traversed by a user. Some conventional systems include an array of force sensors located within the footwear to measure forces exerted during human locomotion. These measured forces are used to assist with the design and manufacture of shoes or running surfaces. Force sensors may also be used to measure speed, distance, or jump time of a user. Other conventional systems for monitoring legged locomotion use one or more accelerometers coupled to footwear of a user. Such accelerometer-based systems also measure speed and distance of the user during activity.
The system and method of the present disclosure provides a measurement of power exerted by a body during legged locomotion. In the present system and method, both force sensors and acceleration sensors are provided. Outputs from both the force sensors and the accelerometers are then used to calculate power generated by the body during legged locomotion. Power generated is a more useful factor to monitor than speed, acceleration, or force. The present system and method may be used by a plurality of different users including humans, animals, or legged machines such as robots which undergo legged locomotion. The calculated power may be provided to various output devices, such as a display, or stored for the duration of an exercise activity and analyzed later.
In an exemplary embodiment of the present disclosure, a method is provided for calculating power generated by a body during legged locomotion. The method comprises providing at least one accelerometer to measure acceleration of the body during legged locomotion, providing at least one force sensor to measure a plurality of propulsive force impulses created by the body during legged locomotion, and calculating the power generated by the body during legged locomotion using output signals from both the at least one accelerometer and the at least one force sensor.
In another exemplary embodiment of the present disclosure, a system is provided to calculate power generated by a body during legged locomotion, The system comprises at least one accelerometer to measure acceleration of the body during legged locomotion, at least one force sensor to measure a plurality of propulsive force impulses created by the body during legged locomotion, and a processor configured to calculate the power generated by the body during legged locomotion using output signals from both the at least one accelerometer and the at least one force sensor.